Try it
ENT · Airway: bronchial foreign body
Sample itemA child with a peanut in the right bronchus has hyperinflation of the right lung and the mediastinum shifts toward the left on expiration. What is the mechanism?
Original practice item, not a recalled exam question. Nothing here is recorded.
The answer and the reasoning
B. Ball-valve obstruction trapping air in the lung
Air enters on inspiration around the foreign body but cannot leave on expiration, so the affected lung stays inflated and pushes the mediastinum away on expiration (Holzknecht's sign). Complete obstruction causes collapse instead.
Option by option
A. Tension pneumothorax
A tension pneumothorax is a different mechanism.
B. Ball-valve obstruction trapping air in the lung (correct)
Correct. A ball-valve effect causes obstructive emphysema.
C. Pleural effusion
An effusion would opacify the hemithorax.
D. Complete obstruction with collapse
Complete obstruction would collapse the lung and shift the mediastinum toward it.
Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.
More ENT questions
- AudiologyIn a tuning fork test, Rinne is negative (bone conduction louder than air conduction) in…
- EarWhich type of chronic suppurative otitis media is considered 'unsafe'?
- LarynxIn singers, vocal nodules typically occur at:
- Vestibular disordersA patient has recurrent attacks of vertigo lasting hours, with fluctuating low-frequency…